Use of an Image-Guided Robotic RadiosurgerySystem for the Treatment of CanineNonlymphomatous Nasal Tumors

摘要

An image-guided robotic stereotactic radiosurgery (SRS) system can be used to deliver curative-intent radiation in eithersingle fraction or hypofractionated doses. Medical records for 19 dogs with nonlymphomatous nasal tumors treated withhypofractionated image-guided robotic stereotactic body radiotherapy (SBRT), either with or without adjunctive treatment,were retrospectively analyzed for survival and prognostic factors. Median survival time (MST) was evaluated using Kaplan-Meier survival curves. Age, breed, tumor type, stage, tumor size, prescribed radiation dose, and heterogeneity index wereanalyzed for prognostic significance. Dogs were treated with three consecutive-day, 8–12 gray (Gy) fractions of imageguidedrobotic SBRT. Overall MST was 399 days. No significant prognostic factors were identified. Acute side effects wererare and mild. Late side effects included one dog with an oronasal fistula and six dogs with seizures. In three of six dogs,seizures were a presenting complaint prior to SBRT. The cause of seizures in the remaining three dogs could not bedefinitively determined due to lack of follow-up computed tomography (CT) imaging. The seizures could have been relatedto either progression of disease or late radiation effect. Results indicate that image-guided robotic SBRT, either with orwithout adjunctive therapy, for canine nonlymphomatous nasal tumors provides comparable survival times (STs) to dailyfractionated megavoltage radiation with fewer required fractions and fewer acute side effects.